Valve for fluid-motors.



No. 802,801. PTENTED OCT. 24, 190

T. C. DUNLAP. VALVE FOR FLUID MTORS.

APPLICATION FILED JULY 25. 1904.

5D 0 9 1l 4v 2 T.. C 0 D E T N E T A P T. C. DUNLAP.

VALVE POR FLUID MOTORS.

APPLICATION FILED JULY 25. 1904.

3 SHEETS-SHEET 2.

511A/wwwa dem lanZa PATENTBD 00T. 24, 1905.

T. C. DUNLAP. VALVE FOR FLUID MOTORS.

APPLICATION FILED JULY 25. 1904.

3 SHEETS-SHEET 3.

INF

wim/woes tiNlED, STAES FATENT OFFICE.

THADDEUS C. DUNLAP, OF COLUMBUS, OHIO.

VALVE FOR FLUID-MOTORS..

ivo. 802,801.

Specification of Letters Patent.

Patented Oct. 24, 1905.

pplicatiou filed July 25, 1904. Serial N0- 218,05

To all 7,071,017?, it 77u07/ con/067177,:

Be it known that l, THADDnUs O. DUNLAP, a citizen ot' the United States, residing at Ooluinbus, in the county ofv Franklin `and State of Ohio, have invented certain new1 and useful Improvements in Valves for Fluid-Motors; and l do hereby declare the following to be a full, clear, and exact description of the inven-` tion, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to a motor mechanism ot' the kind shown in the United States Letters Patent issued to Ulrich and VVittke February 5. 1901, No. 667,350. Where a valve t'or controlling the ports to the cylinders is directly operated, as by the tappet lever or shifter 12 in said patent, great accuracy in the construction and fitting ot' the parts is necessary. To overcome the necessity lor such nicety in construction and fitting of parts and to secure greater certainty in operation. 1 propose to provide in such mechanism an auxiliary valve to beoperated mechanically to effect a pneumatic operation ot' the main valve.

The invention consists in the construction hereinafter described and claimed.

,In the accompanying drawings, Figure 1 isa longitudinal sectional view taken on the plane :1f Fig. 3, some parts being in t'ull. Fig. 2 is-a sectional view on the plane 3/ y, Fig. 1, some parts being in full. Fig. 3 is a side view of the exterior. Fig. 4 is an end view oi' the frame with the cylindersection removed. Fig. 5 is an end view of the cylinder-section. Fig. 6 is a sectional View on a magnified scale of the main and auxiliary valves.

As in the former patent herein referred to, the present mechanism has cross-heads 2 2, with inclined ways 3 3 and toothed rack portions 4 4, a shaft 7 Vfor the tool, symmetricallytoothed heads 8 On arms 8 rocked by the cross-heads, clutches 9 sliding on the shaft 7 and spring 10 for pressing the clutches into the heads 8, a toothed Wheel 11 between the racks 4 4 to equalize the operation ot' the arms 8, and a tappet or shifting lever 12, fulcrurnedl at 12u to be intermittently rocked by a pin 13 on one ot' the reciprocating cross-heads 2. In the present invention, however, 1 show the cylinders 14 14 with pistons 14 14, having appropriate rods 1 connected with the crossheads 2 2 for reciprocating them. 15 designates the inlet for the motor iiuid-for example, air-and 16 16 passages, with appropriate ports 17 connecting said passages and the ends of the cylinders. l/Vithin the main frame, near its junction with the cylinder-section, is cast a casing'118, in which is litted a cylindrical bushing 19, held in position 4by threaded caps 20, thus forming a valve-chamber. The bushing has an opening 191L in the middle of one side coinciding with the inlet 15, and openings 19') coinciding with the passages 16 16, and openings 19, that communicate with the exhaust-ports 19C". (See Fig. Sliding within the bushing is the main valve 22, having a narrow central annular groove 22, with through-ports 22", and beyond this on either side a wide annular groove 22C, adapted to connect the inlet 15 with one oi' the passages 16 and the other passage 16 with an exhaust 19c and 19C". Said main valve also has, at each end beyond the exhaust, ports or openings 22d coinciding with the exhaustpassages 19c and 190C.

Fitting and sliding within the main valve is the auxiliary valve 23, having at its middle a ridge 23, at each side of which are wide annular grooves 23" and at each end narrow annular grooves 23'. r1`he grooves 23" and 23" are connected by longitudinal grooves 23, extending to the ends of the auxiliary valve. The grooves 23" are so located with respect to the ridge 23 that when that ridge closes the ports 22b the grooves 23c are also closed, but when the ridge is just olf said ports 22" at one side the groove 23c at the corresponding side coincides with the exhaust-opening 22d at that side.

The casing 18 and bushing 19 are made with coinciding openings, through which an end of the tappet or shitting lever 12 passes into a socket or hole in the auxiliary valve into engagement with the valve. The openings in the casing 13 and bushing 19 are made large enough to permit the end of the shifting-lever 12 to throw the auxiliary valve independently of the main valve to such an extent as to move the ridge 23 beyond the ports 22" in either direction and the proper groove 23 into coincidence with the proper port 22d.

r1`he operation therefore is as follows: Referring to Figs. 1 and 2.and 6 and assuming that the parts are in the position seen in those views and that the cross-head in the upper part of Fig. 1 is moving inward. the auxiliary valve will be shifted downward by the tappet, so as to take the ridge 23ll oil the port 22 and bring thegroove 23c opposite the port 22d. This will let pressure in the inlet 15 into the vIOO TIO

upper portion of the valve-chamber, thereby forcing the main valve down, the air in the lower part of said chamber exhausting through the lower groove 23C, port 22d, and port 19 and 19. vWhen the main valve is thus thrown, the lower wide groove 22C is brought to coincide both with the passage 19b and the exhaust 19, and the upper wide groove 22C is brought to Coincide both with the inlet l5 and the upper passage 16. The pressure is thus admitted to one end of each cylinder and exhausted from the other, as will be readily understood by those versed in the art to which this invention appertains. The upstrole of the operative end of the tappet effects the same result, except that the direction of the pressure on the valve and the pistons is reversed, as will he readily understood.

lith this invention it will be observed that the operation of the main valve will be prompt and positive. In order to admit the proper quantity of air and at the same time be capable of sustaining the strain of operation at a high speed, the main valve should be of considerable size and weight. By the construction proposed the tappet or shifter is relieved of the strain of working the main valve and the burden put upon the operating Huid. The main valve can therefore be of ample size and weight.

Another important advantage of the presl ent construction is that the movement of the main or controlling valve is independent of the piston speed, giving' an instantaneous and full opening of the ports whether the speed of the piston be slow or fast.

Vhat I claim, and desire to secure by Letters,l Patent, is

In a Jduid-pressure motor, the combination with the ports of the supply, exhaust and working passages thereof, of a main tubular valve for controlling' said ports having the through-passages 22h and 22d and the external annular wide grooves 22C, a solid auxiliaryT valve for controlling the operation of the said main valve having the central annular ridge 23, the wide annular grooves 23, the narrow annular grooves 28C and the longitudinal grooves 23l crossing the grooves 23C and affording' passages from the wide grooves 23b to the ends of the auxiliary and main valves,

and a vibrating arm l2 reaching laterallv` through the main valve and into the auxiliary valve for operating the same, substantially as described.

In testimony whereofl l affix my signature in presence of two witnesses.

THADDEUS C. DUNLAP.

Titnessesz BEM. FINCKEL, SAMUEL iV. LATHAM. 

